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» On the Approximability of the Steiner Tree Problem
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MFCS
2001
Springer
13 years 8 months ago
On the Approximability of the Steiner Tree Problem
We show that it is not possible to approximate the minimum Steiner tree problem within 1 + 1 162 unless RP = NP. The currently best known lower bound is 1 + 1 400. The reduction i...
Martin Thimm
TCBB
2010
166views more  TCBB 2010»
13 years 2 months ago
Approximate Maximum Parsimony and Ancestral Maximum Likelihood
— We explore the maximum parsimony (MP) and ancestral maximum likelihood (AML) criteria in phylogenetic tree reconstruction. Both problems are NP hard, so we seek approximate sol...
Noga Alon, Benny Chor, Fabio Pardi, Anat Rapoport
COCOA
2009
Springer
13 years 10 months ago
A PTAS for Node-Weighted Steiner Tree in Unit Disk Graphs
Abstract. The node-weighted Steiner tree problem is a variation of classical Steiner minimum tree problem. Given a graph G = (V, E) with node weight function C : V → R+ and a sub...
Xianyue Li, Xiao-Hua Xu, Feng Zou, Hongwei Du, Pen...
COCOON
2005
Springer
13 years 9 months ago
Algorithms for Terminal Steiner Trees
The terminal Steiner tree problem (TST) consists of finding a minimum cost Steiner tree where each terminal is a leaf. We describe a factor 2ρ−ρ/(3ρ−2) approximation algor...
Fábio Viduani Martinez, José Coelho ...
ALGORITHMICA
2005
99views more  ALGORITHMICA 2005»
13 years 3 months ago
Improved Approximation Algorithms for the Quality of Service Multicast Tree Problem
Abstract. The Quality of Service Multicast Tree Problem is a generalization of the Steiner tree problem which appears in the context of multimedia multicast and network design. In ...
Marek Karpinski, Ion I. Mandoiu, Alexander Olshevs...